Food products have been produced for many years from grains and various grain products have been produced in expanded form, such as puffed wheat and puffed rice. Many snack foods and breakfast cereals are known which are made from dough, including ground grain, which is expanded in various ways including extrusion. Generally, such products do not provide balanced nutrition or serve dietary purposes. However, one outstanding dietary product has been manufactured from whole wheat and is disclosed in U.S. Pat. Nos. 4,254,359 and 4,438,146. Thus, product has been sold and marketed under the trademark NUTRI-WHEAT by Spicers International and has been established as an outstanding dietary product. See: Use of an Expanded-Whole-Wheat Product in the Reduction of Body Weight and Serum Lipids in Obese Females, by Marianna K. Fordyce-Baum, et al, The American Journal of Clinical Nutrition, 1989; 50:30-6.
Recently, oat bran has been identified as a highly desirable food. Oat bran has been found to lower or eliminate insulin requirement for diabetics. Oat bran helps to prevent heart disease and serves to limit the development of arteriosclerosis. The use of oat bran in the diet provides dietary supplements which have been found very effective for many diseases. The work of Dr. James Anderson is particularly notable, some of which is reported in Journal of the Canadian Dietetic Association, Vol. 45, No. 2, Apr. 1984; The American Journal of Clinical Nutrition 40: pp. 1146-1155, Dec. 1984; Nutrition and Diabetes, Chapter 8, 1985; and Nutrition Update, Vol. 2, Chapter 3, 1985. Oat bran in expanded form would be particularly desirable for human ingestion because of its therapeutic effects in such form. Expanded oat bran serves to sensitize insulin receptors, particularly in muscle. Oat bran slows down transport of food in the intestinal tract, and particularly in the small intestine, and serves to promote desired fermentation in the colon and lower cholesterol and blood pressure.
In summary, it is most desirable for humans to ingest oat bran in expanded form. It is also known that humans should ingest substantial amounts of soluble dietary fiber and oat bran includes significant amounts of soluble dietary fiber and corn bran includes large amounts of dietary fiber a substantial portion of which is soluble dietary fiber. However, products with significant amounts of soluble dietary fiber are difficult to expand, and oat bran and corn bran do not lend themselves to expansion from known doughs by known processes.
Further, oat bran does not in itself offer a balanced meal and it would be desirable to provide oat bran in human diets in a nutritionally balanced product and in an expanded form.
The problem of manufacture of an expanded snack product from bran or an oat cereal is exemplified in U.S. Pat. No. 4,620,981 to Gordon, et al. In this patent, a method is disclosed for making a highly expanded porous oat product. The method is complex and includes the step of classifying an oat flour, i.e., an oat flour produced from oat groats, to separate out a low beta-glucan oat flour with a beta-glucan content of less than about 3.3 percent. In other words, this patent recognizes the difficulty of producing an expanded snack product from oats which contain a substantially high level of beta-glucan in the form of soluble fiber. Further steps of this patent include cooking a mix comprising the low beta-glucan oat flour portion comprising at least about 55 percent of cereal flour in the mix, expanding and shaping the cooked mix into a shaped cereal product, heat setting the shaped cereal product to a moisture content at which it is structurally stable. The final moisture content is indicated to be at a level of from 2 to 4 percent.
U.S. Pat. No. 4,759,942 to Von Fulger describes a process for producing a ready-to-eat cereal, which is expanded cereal dough which incorporates a bran material having a specific average particle size of from 5 to 100 microns. The expanded cereal has a specific density of from 0.15 to 0.40 gms/cc. The process of the Von Fulger patent indicates that the cereal doughs of the process require the use of higher moisture levels (16-30%) than conventional cereal doughs (14-18%) which are intended to be expanded. There is no specific description in the Von Fulger patent of a process to produce an expanded product having a high level of oat bran and the examples relate only to a process for producing an expanded cereal product from micromilled wheat bran.
It is acknowledged that there are many food products available in the food industry which are derived from grains such as wheat, rice, corn, oats and the like to provide dietary products, food supplements and snack foods. Various pieces of equipment and processes have been developed to expand grain products to provide several types of food products, such as ready-to-eat cereals and snack foods. Snack foods have been provided heretofore in expanded form wherein the product is either first cooked to provide a dough which is later extruded or which is provided as an uncooked dough which is cooked in an extruder. The expansion of gas or steam within the dough as it exits out of the extruder from a zone of high pressure to a zone of low pressure results in the formation of an expanded food product. Food products which are from high protein wheat are disclosed in U.S. Pat. No. 4,259,359 and in U.S. Pat. No. 4,438,146.
U.S. Pat. No. 4,526,800 to Howard discloses cereal snack foods in expanded form which are prepared from a dough which includes cooked portions of a dough composition which includes gelatinized starch. The dough composition also includes a minor amount of cereal bran which has been heat-treated to destroy the amylase therein. The bran is selected from common cereal brans, other than rice bran. Reduction of the amylytic activity of the bran is required as well as the presence of 5 percent by weight of oil. Cereal bran, is, of course, only a part of the whole cereal seed, which also includes endosperm and germ.
U.S. Pat. No. 4,315,954 to Kuipers et al. discloses a dietary snack product which includes a fiber containing substance, such as wheat bran. The fiber containing substance is mixed with a protein which is plastifiable to a gel under extruding conditions, such as milk protein (casein). The use of such plastifiable proteins in the presence of small quantities of sugars lead to enzymatic browning under the temperature and extrusion conditions required to provide an expanded snack product. Furthermore, since all proteins have considerable water binding capacity, the incorporation of a protein gel into a dough leads to considerable difficulty in releasing the amount of water required to form an expanded cereal product.
The prior art methods and processes, however, have not provided successful and convenient techniques for the processing of doughs wherein a major amount of the cereal portion is provided from oat bran and corn bran, i.e., high sources of soluble fiber, to make them into balanced dietary products.
Accordingly, a principle object of the present invention is to provide an improved dietary product for human consumption.
A further object of the invention is to provide a balanced dietary product which comprises a high level of soluble dietary fiber and a substantial amount of oat bran.
A still further object of the invention is to provide a method for making improved dietary expanded product which can be processed in conventional equipment.
Still further objects and advantages of the invention can be learned from the following disclosure.